Flash Flood in California, July 7, 2001

Name: Flash Flood in California, July 7, 2001
Start: 2001-07-07T12:30
End: 2001-07-07T13:40
Location: California

July 7, 2001 · NWS SGX · 1 event in 1 county or zone

Spotters observed three inches of rain in 90 minutes. Highway 2 had mud and rock slides, and Lone Pine Canyon Road at Sheep Creek was flooded by 18 inches of water.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

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Floods
Wind
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Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
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The toll

Deaths: 0
Injuries: 0
Property damage: $50,000
Crop damage: None recorded
Events: 1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS SGX wrote it up.

Spotters observed three inches of rain in 90 minutes. Highway 2 had mud and rock slides, and Lone Pine Canyon Road at Sheep Creek was flooded by 18 inches of water.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS San Diego, CA wrote its last area forecast discussion before the first event at Jul 7, 8:30 AM PST, 4 hours earlier.

Area forecast discussion, Jul 7, 8:30 AM PST, 4 hours before

EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 AM PDT SAT JUL 7 2001

                             ...SYNOPSIS...

THUNDERSTORMS WITH HEAVY RAIN ARE EXPECTED AGAIN OVER THE MOUNTAINS AND
DESERTS INTO THIS EVENING...AND A FLASH FLOOD WATCH IS IN EFFECT. THERE
COULD ALSO BE SOME SHOWERS AND THUNDERSTORMS WEST OF THE MOUNTAINS
TODAY. DRIER SOUTHWEST FLOW ALOFT WILL BRING A DECREASING CHANCE OF
MOUNTAIN AND DESERT THUNDERSTORMS EARLY NEXT WEEK. A SHALLOW MARINE
LAYER WILL CAUSE AREAS OF NIGHT AND MORNING COASTAL LOW CLOUDS AND
FOG...OTHERWISE FAIR.

                             ...DISCUSSION...

LOTS OF MID AND HI LEVEL DEBRIS CLOUDS AROUND THIS AM AND AREAS OF LOW
CLOUDS/FOG NEAR COAST. 12Z NKX SOUNDING NOT QUITE AS WET AS 24 HOURS
PREVIOUS BUT STILL SHOWED MOIST LAYER FROM ABOUT 770 MB TO 500 MB WITH
SLY WINDS THROUGH COLUMN. WEAK ONSHORE GRADIENTS WITH ABOUT 3 MB
SAN-IPL.

MAIN FORECAST PROBLEM AGAIN TODAY WILL BE THUNDERSTORMS WITH HEAVY RAIN
AND THE POTENTIAL FOR FLASH FLOODING. A VORT MAX IS EXPECTED TO MOVE
THROUGH FROM THE SW AND MAY HELP CAUSE A FEW MORE SHOWERS W OF THE
MOUNTAINS TODAY. OTHERWISE...THERMAL AND MECHANICAL LIFT OVER MOUNTAIN
AND DESERTS WILL KEEP THEM THE PREFERRED AREAS FOR FLASH FLOODING THIS
AFTERNOON/EVE...ESPECIALLY ON THE S TO SW FACING MOUNTAIN SLOPES. SHOULD
BE INTO NVA LATE TONIGHT FOR DECREASING SHOWERS/THUNDERSTORMS. DRIER SW
FLOW ALOFT DEVELOPS SUNDAY FOR AN END TO THE THREAT OF SHOWERS/
THUNDERSTORMS W OF MOUNTAINS BUT STILL ENOUGH RESIDUAL LOW LEVEL
MOISTURE FOR SOME MENTION IN THE MOUNTAINS/DESERTS WITH EVEN LESS CHANCE
ON MON. GRADUALLY INCREASING HEIGHTS/THICKNESS/850 MB TEMPS AND LESS
CLOUD COVER FOR WARMING IN MOST AREAS. HOWEVER...INCREASING ONSHORE
GRADIENTS TO INTENSIFYING DESERT THERMAL LOW WILL MODERATE MAX TEMPS
NEAR THE COAST. A SHALLOW MARINE LAYER WILL RESULT IN SOME NIGHT/MORNING
COASTAL LOW CLOUDS/FOG.

LONGER RANGE PROGS MAINTAIN DRY SW FLOW ALOFT THROUGH MID WEEK BUT WITH
POSSIBLE WEAK ELY WAVE TUE. UPPER HI SLOWLY BUILDS BACK OVER THE SW
TOWARD THE END OF THE WEEK WITH FLOW ALOFT TURNING MORE SLY AGAIN. WILL
LEAVE IN SOME MOUNTAIN/DESERT THUNDERSTORMS...OTHERWISE FAIR WITH NIGHT/
MORNING COASTAL LOW CLOUDS AND MINOR TEMP CHANGES.

.SAN...FLASH FLOOD WATCH UNTIL 9 PM FOR MOUNTAINS AND DESERTS
       CAZ055-056-058-060-061-062...SEE LA]XFFASAN.

ATKIN

In the hours before

Local storm report, Jul 7, 6:45 AM PST, 5 hours 45 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN DIEGO, CA
745 AM PDT SAT JUL 7 2001

TIME(PDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1100 AM    MONTCLAIR                 CA   LIGHTNING DAMAGE
07/06/01   SAN BERNARDINO                 A BOLT OF LIGHTNING STRUCK A
                                          A FURNITURE STORE. DAMAGE WAS
                                          ESTIMATED AT $840,000.

1100 AM    FONTANA                   CA   TSTM WIND GUST
07/06/01   SAN BERNARDINO                 POWER LINES WERE BLOWN DOWN
                                          IN FONTANA AND CHINO.

1110 AM    RANCHO CUCAMONGA          CA   LIGHTNING INJURY
07/06/01   SAN BERNARDINO                 A 33 YEAR OLD MAN WAS THROWN
                                          5 FEET WHEN LIGHTNING STRUCK
                                          A CEMENT TRUCK HE WAS WORKING
                                          NEXT TO. THE TRUCK DRIVER WAS
                                          NOT INJURED.

1300 PM    BIG BEAR LAKE             CA   URBAN FLOODING
07/06/01   SAN BERNARDINO                 FLOODING OF ROADS AROUND
                                          BIG BEAR LAKE AND LAKE
                                          ARROWHEAD. SPOTTERS OBSERVED
                                          HEAVY RAIN DURING A 5 MINUTE
                                          PERIOD.

1400 PM    MORONGO VALLEY            CA   URBAN FLOODING
07/O6/01   SAN BERNARDINO                 FLOODING ALONG HIGHWAY 62
                                          WAS REPORTED FROM A
                                          THUNDERSTORM.

1600 PM    2 S PALM SPRINGS          CA   FLASH FLOOD
07/06/01   RIVERSIDE                      FLOODING ALONG PALM CANYON
                                          WASH BETWEEN ARABY STREET
                                          AND CATHEDRAL CANYON DRIVE.
                                          WATER WAS FLOWING FAST AND
                                          DEEP ACROSS ROADS.

RB

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 flash flood. Local standard time, as filed.

Flash Flood, San Bernardino

When: July 7, 12:30 PM PST to 1:40 PM PST
Where: San Bernardino County, Wrightwood
Property damage: $50,000
Reported by: TRAINED SPOTTER
Coordinates: 34.841, -116.178 (the zone’s center; the record gives no point)

What these are

Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in California in 2001 Every state in 2001 This day in weather history Warnings in California, July 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5258011.